Commit Graph

72 Commits

Author SHA1 Message Date
Fabian Frederick
62aa81d7c4 ocfs2: use magic.h
Filesystems generally use SUPER_MAGIC values from magic.h instead of a
local definition.

Link: http://lkml.kernel.org/r/20170521154217.27917-1-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Reviewed-by: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <jiangqi903@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-06 16:24:30 -07:00
Guozhonghua
8ba442214c ocfs2: fix comment in struct ocfs2_extended_slot
The comment in ocfs2_extended_slot has the offset wrong.

Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-05-19 19:12:14 -07:00
Masahiro Yamada
e1c05067c3 treewide: fix typos in comment blocks
Looks like the word "contiguous" is often mistyped.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>
2015-08-07 14:46:24 +02:00
Mark Fasheh
18d585f0f2 ocfs2: make append_dio an incompat feature
It turns out that making this feature ro_compat isn't quite enough to
prevent accidental corruption on mount from older kernels.  Ocfs2 (like
other file systems) will process orphaned inodes even when the user mounts
in 'ro' mode.  So for the case of a filesystem not knowing the append_dio
feature, mounting the filesystem could result in orphaned-for-dio files
being deleted, which we clearly don't want.

So instead, turn this into an incompat flag.

Btw, this is kind of my fault - initially I asked that we add a flag to
cover the feature and even suggested that we use an ro flag.  It wasn't
until I was looking through our commits for v4.0-rc1 that I realized we
actually want this to be incompat.

Signed-off-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joseph Qi <joseph.qi@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-03-12 18:46:07 -07:00
Joseph Qi
160cc26663 ocfs2: set append dio as a ro compat feature
Intruduce a bit OCFS2_FEATURE_RO_COMPAT_APPEND_DIO and check it in
write flow. If the bit is not set, fall back to the old way.

Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Weiwei Wang <wangww631@huawei.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Xuejiufei <xuejiufei@huawei.com>
Cc: alex chen <alex.chen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-16 17:56:05 -08:00
Joseph Qi
06ee5c75b5 ocfs2: add functions to add and remove inode in orphan dir
Add functions to add inode to orphan dir and remove inode in orphan dir.
Here we do not call ocfs2_prepare_orphan_dir and ocfs2_orphan_add
directly.  Because append O_DIRECT will add inode to orphan two and may
result in more than one orphan entry for the same inode.

[akpm@linux-foundation.org: avoid dynamic stack allocation]
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Weiwei Wang <wangww631@huawei.com>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Xuejiufei <xuejiufei@huawei.com>
Cc: alex chen <alex.chen@huawei.com>
Cc: Fengguang Wu <fengguang.wu@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-02-16 17:56:04 -08:00
Lucas De Marchi
e9c549998d Revert wrong fixes for common misspellings
These changes were incorrectly fixed by codespell. They were now
manually corrected.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-04-26 23:31:11 -07:00
Lucas De Marchi
25985edced Fix common misspellings
Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>
2011-03-31 11:26:23 -03:00
Tao Ma
7d8f98769e ocfs2: Fix system inodes cache overflow.
When we store system inodes cache in ocfs2_super,
we use a array for global system inodes. But unfortunately,
the range is calculated wrongly which makes it overflow and
pollute ocfs2_super->local_system_inodes.
This patch fix it by setting the range properly.

The corresponding bug is ossbug1303.
http://oss.oracle.com/bugzilla/show_bug.cgi?id=1303

Cc: stable@kernel.org
Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-12-22 02:35:36 -08:00
Joel Becker
fc3718918f Merge branch 'globalheartbeat-2' of git://oss.oracle.com/git/smushran/linux-2.6 into ocfs2-merge-window
Conflicts:
	fs/ocfs2/ocfs2.h
2010-10-15 13:03:09 -07:00
Sunil Mushran
2c442719e9 ocfs2: Add support for heartbeat=global mount option
Adds support for heartbeat=global mount option. It ensures that the heartbeat
mode passed matches the one enabled on disk.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
2010-10-07 15:23:50 -07:00
Sunil Mushran
98f486f23b ocfs2: Add an incompat feature flag OCFS2_FEATURE_INCOMPAT_CLUSTERINFO
OCFS2_FEATURE_INCOMPAT_CLUSTERINFO allows us to use sb->s_cluster_info for
both userspace and o2cb cluster stacks. It also allows us to extend cluster
info to include stack flags.

This patch also adds stackflags to sb->s_clusterinfo. It also introduces a
clusterinfo flag OCFS2_CLUSTER_O2CB_GLOBAL_HEARTBEAT to denote the enabled
global heartbeat mode.

This incompat flag can be set/cleared using tunefs.ocfs2 --fs-features. The
clusterinfo flag is set/cleared using tunefs.ocfs2 --update-cluster-stack.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
2010-10-09 10:24:46 -07:00
Tao Ma
0000b86202 ocfs2: Sync inode flags with ext2.
We sync our inode flags with ext2 and define them by hex
values. But actually in commit 3669567(4 years ago), all
these values are moved to include/linux/fs.h. So we'd
better also use them as what ext2 did. So sync our inode
flags with ext2 by using FS_*.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-09-23 14:16:49 -07:00
Tao Ma
b4d693fcc5 ocfs2: Cache system inodes of other slots.
Durring orphan scan, if we are slot 0, and we are replaying
orphan_dir:0001, the general process is that for every file
in this dir:
1. we will iget orphan_dir:0001, since there is no inode for it.
   we will have to create an inode and read it from the disk.
2. do the normal work, such as delete_inode and remove it from
   the dir if it is allowed.
3. call iput orphan_dir:0001 when we are done. In this case,
   since we have no dcache for this inode, i_count will
   reach 0, and VFS will have to call clear_inode and in
   ocfs2_clear_inode we will checkpoint the inode which will let
   ocfs2_cmt and journald begin to work.
4. We loop back to 1 for the next file.

So you see, actually for every deleted file, we have to read the
orphan dir from the disk and checkpoint the journal. It is very
time consuming and cause a lot of journal checkpoint I/O.
A better solution is that we can have another reference for these
inodes in ocfs2_super. So if there is no other race among
nodes(which will let dlmglue to checkpoint the inode), for step 3,
clear_inode won't be called and for step 1, we may only need to
read the inode for the 1st time. This is a big win for us.

So this patch will try to cache system inodes of other slots so
that we will have one more reference for these inodes and avoid
the extra inode read and journal checkpoint.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-09-10 08:56:24 -07:00
Tao Ma
1a934c3e57 ocfs2: enable discontig block group support.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
2010-03-18 15:54:22 +08:00
Tao Ma
af2bf0d860 ocfs2: Add ocfs2_gd_is_discontig.
Add ocfs2_gd_is_discontig so that we can test whether
a group descriptor is discontiguous or not.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
2010-05-17 15:14:17 +08:00
Tao Ma
8571882c21 ocfs2: ocfs2_group_bitmap_size has to handle old volume.
ocfs2_group_bitmap_size has to handle the case when the
volume don't have discontiguous block group support. So
pass the feature_incompat in and check it.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
2010-04-13 14:38:06 +08:00
Joel Becker
9cbc01231e ocfs2: Add suballoc_loc to metadata blocks.
We need a suballoc_loc field on any suballocated block.  Define them.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-26 10:07:42 +08:00
Joel Becker
798db35f46 ocfs2: Allocate discontiguous block groups.
If we cannot get a contiguous region for a block group, allocate a
discontiguous one when the filesystem supports it.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Tao Ma <tao.ma@oracle.com>
2010-04-13 14:26:32 +08:00
Joel Becker
4cbe4249d6 ocfs2: Define data structures for discontiguous block groups.
Defines the OCFS2_FEATURE_INCOMPAT_DISCONTIG_BG feature bit and modifies
struct ocfs2_group_desc for the feature.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Tao Ma <tao.ma@oracle.com>
2010-04-13 14:26:12 +08:00
Mark Fasheh
6b82021b9e ocfs2: increase the default size of local alloc windows
I have observed that the current size of 8M gives us pretty poor
fragmentation on multi-threaded workloads which do lots of writes.

Generally, I can increase the size of local alloc windows and observe a
marked decrease in fragmentation, even up and beyond window sizes of 512
megabytes. This makes sense for a couple reasons - larger local alloc means
more room for reservation windows. On multi-node workloads the larger local
alloc helps as well because we don't have to do window slides as often.

Also, I removed the OCFS2_DEFAULT_LOCAL_ALLOC_SIZE constant as it is no
longer used and the comment above it was out of date.

To test fragmentation, I used a workload which launched 4 threads that did
4k writes into a series of about 140 alternating files.

With resv_level=2, and a 4k/4k file system I observed the following average
fragmentation for various localalloc= parameters:

localalloc=	avg. fragmentation
	8		48
	32		16
	64		10
	120		7

On larger cluster sizes, the difference is more dramatic.

The new default size top out at 256M, which we'll only get for cluster
sizes of 32K and above.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-05-05 18:18:07 -07:00
Tristan Ye
9df5778ece Ocfs2: Move ocfs2 ioctl definitions from ocfs2_fs.h to newly added ocfs2_ioctl.h
Currently we were adding ioctl cmds/structures for ocfs2 into ocfs2_fs.h
which was used for define ocfs2 on-disk layout. That sounds a little bit
confusing, and it may be quickly polluted espcially when growing the
ocfs2_info_request ioctls afterwards(it will grow i bet).

As a result, such OCFS2 IOCs do need to be placed somewhere other than
ocfs2_fs.h, a separated ocfs2_ioctl.h will be added to store such ioctl
structures and definitions which could also be used from userspace to
invoke ioctls call.

Signed-off-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-03-02 14:10:20 -08:00
Tao Ma
1097df3ffe ocfs2: Sync max_inline_data_with_xattr from tools.
In ocfs2-tools, we have added ocfs2_max_inline_data_with_xattr,
so add it in the kernel's ocfs2_fs.h.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2010-01-25 19:20:45 -08:00
Coly Li
9365454016 ocfs2: replace u8 by __u8 in ocfs2_fs.h
This patch replaces date type 'u8' with '__u8', which follows the coding style of ocfs2_fs.h, and portable to user space
for ocfs2-tools.

Signed-off-by: Coly Li <coly.li@suse.de>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
2009-12-17 20:55:54 -08:00
Tao Ma
bd50873dc7 ocfs2: Add ioctl for reflink.
The ioctl will take 3 parameters: old_path, new_path and
preserve and call vfs_reflink. It is useful when we backport
reflink features to old kernels.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
2009-09-22 20:09:51 -07:00
Tao Ma
64871b8d62 ocfs2: Enable refcount tree support.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
2009-09-22 20:09:50 -07:00
Tao Ma
e73a819db9 ocfs2: Add support for incrementing refcount in the tree.
Given a physical cpos and length, increment the refcount
in the tree. If the extent has not been seen before, a refcount
record is created for it. Refcount records may be merged or
split by this operation.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
2009-09-22 20:09:33 -07:00
Tao Ma
721f69c404 ocfs2: Define refcount tree structure.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
2009-09-22 20:09:25 -07:00
Mark Fasheh
3a8df2b9c3 ocfs2: Enable indexed directories
Since the disk format is finalized, we can set this feature bit in the
supported mask.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>
2009-04-03 11:39:16 -07:00
Mark Fasheh
e3a93c2db6 ocfs2: Add total entry count to dx_root_block
This little bit of extra accounting speeds up ocfs2_empty_dir()
dramatically by allowing us to short-circuit the full directory scan.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-04-03 11:39:16 -07:00
Mark Fasheh
198a1ca3b7 ocfs2: Increase max links count
Since we've now got a directory format capable of handling a large number of
entries, we can increase the maximum link count supported. This only gets
increased if the directory indexing feature is turned on.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03 11:39:16 -07:00
Mark Fasheh
e7c17e4309 ocfs2: Introduce dir free space list
The only operation which doesn't get faster with directory indexing is
insert, which still has to walk the entire unindexed directory portion to
find a free block. This patch provides an improvement in directory insert
performance by maintaining a singly linked list of directory leaf blocks
which have space for additional dirents.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03 11:39:16 -07:00
Mark Fasheh
4ed8a6bb08 ocfs2: Store dir index records inline
Allow us to store a small number of directory index records in the
ocfs2_dx_root_block. This saves us a disk read on small to medium sized
directories (less than about 250 entries). The inline root is automatically
turned into a root block with extents if the directory size increases beyond
it's capacity.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03 11:39:16 -07:00
Mark Fasheh
9b7895efac ocfs2: Add a name indexed b-tree to directory inodes
This patch makes use of Ocfs2's flexible btree code to add an additional
tree to directory inodes. The new tree stores an array of small,
fixed-length records in each leaf block. Each record stores a hash value,
and pointer to a block in the traditional (unindexed) directory tree where a
dirent with the given name hash resides. Lookup exclusively uses this tree
to find dirents, thus providing us with constant time name lookups.

Some of the hashing code was copied from ext3. Unfortunately, it has lots of
unfixed checkpatch errors. I left that as-is so that tracking changes would
be easier.

Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
2009-04-03 11:39:15 -07:00
Tiger Yang
d9ae49d6e2 ocfs2: tweak to get the maximum inline data size with xattr
Replace max_inline_data with max_inline_data_with_xattr
to ensure it correct when xattr inlined.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-03-12 16:45:46 -07:00
Joel Becker
9d28cfb73f ocfs2: Enable metadata checksums.
Add OCFS2_FEATURE_INCOMPAT_META_ECC to the list of supported features.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:34 -08:00
Joel Becker
c175a518b4 ocfs2: Checksum and ECC for directory blocks.
Use the db_check field of ocfs2_dir_block_trailer to crc/ecc the
dirblocks.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:34 -08:00
Mark Fasheh
87d35a74b1 ocfs2: Add directory block trailers.
Future ocfs2 features metaecc and indexed directories need to store a
little bit of data in each dirblock.  For compatibility, we place this
in a trailer at the end of the dirblock.  The trailer plays itself as an
empty dirent, so that if the features are turned off, it can be reused
without requiring a tunefs scan.

This code adds the trailer and validates it when the block is read in.

[ Mark is the original author, but I reinserted this code before his
  dir index work.  -- Joel ]

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:34 -08:00
Joel Becker
ab552d5467 ocfs2: Add the on-disk structures for metadata checksums.
Define struct ocfs2_block_check, an 8-byte structure containing a 32bit
crc32_le and a 16bit hamming code ecc.  This will be used for metadata
checksums.  Add the structure to free spaces in the various metadata
structures.

Add the OCFS2_FEATURE_INCOMPAT_META_ECC bit.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:31 -08:00
Jan Kara
19ece546a4 ocfs2: Enable quota accounting on mount, disable on umount
Enable quota usage tracking on mount and disable it on umount. Also
add support for quota on and quota off quotactls and usrquota and
grpquota mount options. Add quota features among supported ones.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:24 -08:00
Jan Kara
9e33d69f55 ocfs2: Implementation of local and global quota file handling
For each quota type each node has local quota file. In this file it stores
changes users have made to disk usage via this node. Once in a while this
information is synced to global file (and thus with other nodes) so that
limits enforcement at least aproximately works.

Global quota files contain all the information about usage and limits. It's
mostly handled by the generic VFS code (which implements a trie of structures
inside a quota file). We only have to provide functions to convert structures
from on-disk format to in-memory one. We also have to provide wrappers for
various quota functions starting transactions and acquiring necessary cluster
locks before the actual IO is really started.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:23 -08:00
Jan Kara
1a224ad11e ocfs2: Assign feature bits and system inodes to quota feature and quota files
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2009-01-05 08:40:23 -08:00
Joel Becker
a97721894a ocfs2: Add JBD2 compat feature bit.
Define the OCFS2_FEATURE_COMPAT_JBD2 bit in the filesystem header.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-12-16 18:26:16 -08:00
Tao Ma
8573f79d30 ocfs2: Fix some typos in xattr annotations.
Fix some typos in the xattr annotations.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Reported-by: Coly Li <coyli@suse.de>
Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-11-10 09:51:46 -08:00
Tiger Yang
8154da3d21 ocfs2: Add incompatible flag for extended attribute
This patch adds the s_incompat flag for extended attribute support. This
helps us ensure that older versions of Ocfs2 or ocfs2-tools will not be able
to mount a volume with xattr support.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 16:57:03 -07:00
Tao Ma
0c044f0b24 ocfs2: Add xattr bucket iteration for large numbers of EAs
Ocfs2 breaks up xattr index tree leaves into 4k regions, called buckets.
Attributes are stored within a given bucket, depending on hash value.

After a discussion with Mark, we decided that the per-bucket index
(xe_entry[]) would only exist in the 1st block of a bucket. Likewise,
name/value pairs will not straddle more than one block. This allows the
majority of operations to work directly on the buffer heads in a leaf block.

This patch adds code to iterate the buckets in an EA. A new abstration of
ocfs2_xattr_bucket is added. It records the bhs in this bucket and
ocfs2_xattr_header. This keeps the code neat, improving readibility.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 16:57:03 -07:00
Tiger Yang
cf1d6c763f ocfs2: Add extended attribute support
This patch implements storing extended attributes both in inode or a single
external block. We only store EA's in-inode when blocksize > 512 or that
inode block has free space for it. When an EA's value is larger than 80
bytes, we will store the value via b-tree outside inode or block.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 16:57:02 -07:00
Tiger Yang
fdd77704a8 ocfs2: reserve inline space for extended attribute
Add the structures and helper functions we want for handling inline extended
attributes. We also update the inline-data handlers so that they properly
function in the event that we have both inline data and inline attributes
sharing an inode block.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 16:57:02 -07:00
Tao Ma
5a7bc8eb29 ocfs2: Add the basic xattr disk layout in ocfs2_fs.h
Ocfs2 uses a very flexible structure for storing extended attributes on
disk. Small amount of attributes are stored directly in the inode block - up
to 256 bytes worth. If that fills up, attributes are also stored in an
external block, linked to from the inode block. That block can in turn
expand to a btree, capable of storing large numbers of attributes.

Individual attribute values are stored inline if they're small enough
(currently about 80 bytes, this can be changed though), and otherwise are
expanded to a btree. The theoretical limit to the size of an individual
attribute is about the same as an inode, though the kernel's upper bound on
the size of an attributes data is far smaller.

Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-10-13 13:57:59 -07:00
Sunil Mushran
c69991aac7 [PATCH 1/2] ocfs2: Add counter in struct ocfs2_dinode to track journal replays
This patch renames the ij_pad to ij_recovery_generation in struct ocfs2_dinode.
This will be used to keep count of journal replays after an unclean shutdown.

Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
2008-07-31 16:21:13 -07:00